There are a variety of trash receptacles taught in the prior art. These are best understood in light of the problems presented by the trash liners of the prior art.
Within the last generation, trash liners that are flexible and collapsible and made from thin plastic film (usually polyethylene) have displaced paper bags, particularly Kraft-type paper bags, as the preferred method of trash disposal. Although they present the advantages of being moistureproof, sealable to prevent the escape of malodorous emanations, and less expensive, the plastic film trash liners are so flexible that they are structurally incapable of supporting themselves in an upright and open position when empty. As a result, the trash liner must be contained within a support structure. Because the liner is so thin, the support structure must not present puncture points which might penetrate the liner. The liners are often used in receptacles with a volume of 20 gallons or more. If the liner is filled to a density of even 10 lbs/ft.sup.3 (about one-sixth the density of water), the liner could weigh almost 27 lbs. When fully expanded within the receptacle, the trash liner will contour itself closely to the interior surface of the receptacle. As the liner is removed from the receptacle, the close fit around the interior circumference is so good that, unless there are internal structures in the receptacle to allow air to flow past the receptacle-liner interface, the liner will act as a piston within a cylinder, and the vacuum created between the trash liner and the receptacle will increase the difficulty in removing the liner. In addition to increasing the difficulty of removal, this increases the probability of tearing the thin liner walls.
Several inventors have suggested their solution to these problems in their patents. For example, U.S. Pat. No. 3,595,507 to Kurlander (Jul. 27, 1971) teaches a rather simple frame composed of rod members that holds the trash liner open and constricts the liner within a generally cylindrical volume.
Aboud, in U.S. Pat. No. 3,927,786 (Dec. 23, 1975), teaches an upright two-piece container that allows the main tubular body of the container to be lifted from the bottom portion. When the trash liner is full, the user removes the container from the trash liner rather than vice versa.
Getz, U.S. Pat. No. 3,964,630 (Jun. 22, 1976), has a container where the filled, closed trash liner is removed by opening the container, the top portion of which is hingedly connected to the bottom portion. The cross-section of the intermediate portion of the container decreases from bottom to top, so that the tendency of the liner to bind to the container is minimized as the hinged intermediate portion is swung off of the bottom portion.
In U.S. Pat. No. 4,054,225 (Oct. 18, 1977), Frech teaches a container where the cylindrical container has a continuous longitudinal slit therealong, with latching means provided on either side of the slit. The filled liner is released from the container by opening the latching means, effectively increasing the container volume.
Peterson, in U.S. Pat. No. 4,140,257 (Feb. 20, 1979), attacks the problem by using a sling that is placed in a conventional container before the trash liner. The webs of the sling are attached to each other once the trash liner is filled, and they provide additional strength to the trash liner, as well as lifting the liner away from the container walls.
Boynton, U.S. Pat. No. 4,254,602 (Mar. 10, 1981), teaches a device that compacts the trash into a plug that is somewhat smaller than the trash liner. This device is then inserted into the trash liner, rather than vice versa, and the transfer from device to liner is accomplished.
In U.S. Pat. No. 4,294,379 (Oct. 13, 1981), Bard teaches a container with internally positioned vertical tubes to allow air to flow to the vacant space below the trash liner to assist in removing the trash liner from the container.
Kehl, in U.S. Pat. No. 4,416,197 (Nov. 22, 1983), teaches a container for allowing compaction of trash within a trash liner. The container has apertures to allow air to be expelled from the space between the liner and the container. The container is also equipped with a circumferential recess or a flange near or at the bottom surface of the container to allow a foothold in filling the liner or removing it from the container.
Campbell, U.S. Pat. No. 4,440,321 (Apr. 3, 1984), adapts the concept of Boynton '602 by designing a container that is filled with trash which is compacted therein before the trash is deposited in a trash liner that fits over rather than within the container.
Copeland, U.S. Pat. 4,643,380 (Feb. 17, 1987), teaches a container in the style of Aboud '786; that is, the container is removed from the filled trash liner rather than vice versa.
Lounsbury teaches a trash receptacle that opens on the side so that the filed bag need not be lifted out of the receptacle, in U.S. Pat. No. 4,923,080 (May 8, 1990).
Roesch, U.S. Pat. No. 4,951,831 (Aug. 28, 1990), teaches a plastic trash receptacle that has a plurality of longitudinal slots, as opposed to the single longitudinal slit of Frech. Also, the slots do not extend completely to the top end of the container. Roesch teaches the use of outwardly extending toe holds to assist in removing the liner from the receptacle.